Insulin sensitivity factor (ISF) can be estimated and measured. Estimate with the 1800 rule for rapid‑acting insulin (1800 ÷ total daily insulin = mg/dL lowered per unit; 1500 for regular insulin). To test, in stable conditions check glucose, give a known small bolus, then monitor BG (or CGM) every 30–60 minutes for 2–4 hours to observe the drop. Do this with clinician guidance.

Signs of poor insulin sensitivity include high fasting blood glucose or HbA1c, elevated fasting insulin or HOMA‑IR, weight gain—especially abdominal fat, difficulty losing weight, fatigue or hunger after meals, increased thirst and urination, and darkened skin patches (acanthosis nigricans). Confirm with blood tests (fasting glucose, HbA1c, oral glucose tolerance, fasting insulin) and lipid abnormalities; consult your healthcare provider for diagnosis and management.

Insulin sensitivity is assessed by several tests. A fasting glucose and insulin level can calculate HOMA‑IR (higher values = resistance). An oral glucose tolerance test (OGTT) with insulin measurements shows dynamic response. The euglycemic‑hyperinsulinemic clamp is the gold standard in research. Continuous glucose monitoring and mixed‑meal tests can give practical insight. Discuss testing and interpretation with your clinician.

Insulin sensitivity is often evaluated using HOMA‑IR; values below about 1.0 are considered optimal, 1.0–1.9 generally healthy, 2.0–2.9 borderline, and ≥3.0 suggests insulin resistance. Supporting labs include fasting insulin roughly 2–20 μIU/mL and fasting glucose <100 mg/dL. Interpretation varies by lab and individual, so clinical assessment and repeat testing are recommended.

Reduced insulin sensitivity (insulin resistance) is linked to type 2 diabetes and prediabetes, metabolic syndrome, obesity, nonalcoholic fatty liver disease (NAFLD), cardiovascular diseases (atherosclerosis, coronary artery disease), hypertension, polycystic ovary syndrome (PCOS), certain cancers (breast, colorectal), and cognitive decline including Alzheimer’s disease. Improving insulin sensitivity lowers risk and is central to prevention and management of these conditions.

In India the HOMA‑IR is usually calculated from fasting insulin and glucose tests. Fasting insulin costs about ₹400–1,500; fasting glucose about ₹50–200. So total lab costs typically range ₹450–1,700 depending on city and lab. Prices vary by private vs hospital labs; online discounts often lower costs.